Drove the XJ6 this afternoon; the same approximately 30 mile round-trip, and she really ran pretty good: started right up, idled OK, etc. When I arrived and shut down for about 30 mins, I had to crank through 4 or 5 C-H-D episodes before she kept running, then I drove toward home, stopped to buy a news paper and left it idling, 5 mins. when I put her in gear, she died, then c-h-d for a couple minutes before she caught.
Got her home without any problem, then after a few hours went to garage her, and C-H-D until I gave up. Went back a couple hours later, she started and ran on about the second try, and garaged her. When she's on the road, she has not made one bobble and she runs very smoothly.
I noticed: when I have C-H-D: if I keep the starter engaged, it will keep hitting about every 1/2 to one second, with a pretty steady interval between "hit" episodes, almost like the ignition is coming in and out. I can hold the key to "crank" with the transmission in R and hear the fuel pump running steadily, so I think it's ignition-related. Also, it seems to make no difference If I apply different amounts of throttle, or just keep my foot off altogether. When se decides to run, shen cranks the normal length of time and then starts and runs normally as if nothing were wrong.
The C-H-d also seems to be more pronounced when the engine is warmed up, which also leads me to some sort of temperature related fault in an electronic component.
Oh, and by the way: I tried the cruise control and it seemed to work perfectly. That leaves the air conditioning compressor as the only non-working thing I've found, so far. I have not dared try the sunroof yet.

 

Run a jumper wire from the battery "+" post to the coil "+" post and do for a drive. Let us know if anything changes.




Both the ignition module (AC Delco part number D1906) and the coil are known to give problems...especially after they've soaked up some engine heat.

Cheers
DD

 

Tremendous info; Thanks!
One question: what is the physical location of the AC Delco module (D 1906)? I have a Haynes manual and I can't find an illustration of this device.
Thanks again!
RR

 

The module is inside the ignition amplifier. The amplifier is the black box bolted to the front of the intake manifold

Cheers
DD

 

also, you can fallow the two 12v wires from the distributor, they plug directly into the electronic ignition amplifier, easy way to locate it. I always suggest a new coil, makes a big difference on these cars. another tip, you can purchase a pertronix distributor that will completely bypass the ignition amp and module elevating future problems in the ignition system. for both the pertronix coil and distributor it is about $200 on amazon.com but it is well worth it, more horse power, better fuel economy and smoother idle, oh and quicker starts! you'll want the 40000v 1.5-3.ohm coil with the d177600 distributor.
best of luck to you.